Geez, I almost forgot! Well, a little bit on purpose, actually. 'Member that System Shock Retrospective article on GameSpot I linked to, where it said that there would be a System Shock-related announcement soon from the makers of System Shock 2? Well, it's more related to just the word "shock". BioShock isn't a sequel to SS2. At the very most it could be considered a very tenuous prequel, as it's not set in the spaceship-y, psychotic artificial intelligence-y future.

Get this: it's got World War II in it. OK, it's just set in an abandoned WWII infirmary. But I think that still counts it as another WWII game. As for the gameplay, well this guy nailed what's wrong with the premise. Good job, this guy.

BioShock First Look [GameSpot]
System Shock 2 Retrospective [Kotaku]